Kentucky bluegrass

ABSTRACT

A variety of Kentucky bluegrass having a high level of disease resistance, good turf performance, and a very high level of seed yield potential.

BACKGROUND

Kentucky bluegrasses have been disclosed in U.S. Plant Pat. No. 3,156 which issued on May 9, 1972; U.S. Plant Pat. No. 3,186 which issued on May 23, 1972; U.S. Plant Pat. No. 4,336 which issued on Nov. 28, 1978; U.S. Plant patent application, Ser. No. 872,537, filed June 10, 1986; U.S. Plant patent application, Ser. No. 910,146, filed Sept. 19, 1986; U.S. Plant patent application, Ser. No. 27,285, filed Mar. 17, 1987 and U.S. Plant patent application, Ser. No. 28,424, filed Mar. 17, 1987.

SUMMARY OF THE VARIETY

The present invention relates to a new and distinct variety of Poa pratensis that has been designated Ba 72-441 Kentucky bluegrass.

Ba 72-441 plant material originated by crossing a Kentucky bluegrass plant ("Victa") disclosed in U.S. Plant Pat. No. 3,156, the seed parent, with a Kentucky bluegrass plant ("Windsor") disclosed in U.S. Plant Pat. No. 2,364, the pollen parent. As a result of this breeding, a distinct variety was produced and asexually propagated by rhizomes, tillers and disseminules. Seed of Ba 72-441 was produced first at Marysville, Ohio and later at Gervais, Oreg. This seed was used to plant turf performance evaluation trials.

Asexual reproduction of Ba 72-441 by propagules (tillers and rhizomes) and by disseminules (modified caryopses produced by apomixis) has consistently produced progeny plants indistinguishable from the mother plant.

Ba 72-441 has a number of highly desirable characteristics including a good level of resistance to Helminthosporium spp. that causes leaf spot, melting out and crown rot, Ustilago striiformis that causes stripe smut, and Puccinia spp. that causes rust; an attractive leafy turf type growth habit; moderately wide leaf blades; an attractive green color which can be maintained throughout the entire growing season; good turf performance as evidenced by consistently high scores in tests throughout the U.S.A.; and a very high seed yield potential in the bluegrass seed production region of the U.S.A.

In comparison with its seed parent, the new variety has a thinner peduncle, a more narrow and thinner flag leaf, and better winter color. In comparison to the pollen parent, the new variety has fewer seeds per pound and a higher seed yield.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a photograph of Ba 72-441 Kentucky bluegrass plant in the vegetative stage including the extensive root and rhizome system;

FIG. 2 is a photograph of Ba 72-441 Kentucky bluegrass panicle;

FIG. 3 is a photograph of Ba 72-441 Kentucky bluegrass seed; and

FIG. 4 is a photograph of Ba 72-441 Kentucky bluegrass turf.

DETAILED DESCRIPTION OF THE VARIETY

Ba 72-441 Kentucky bluegrass (Poa protensis L.) is perennial with creeping rhizomes forming a moderately dense turf. When plants overwinter in the field with freezing temperatures and then are brought into the greenhouse during late winter to continue growth undisturbed by clipping under moderate temperatures (60°-80° F.), culms are erect averaging 421 mm in length with an average of 2.7 nodes per culm. The uppermost internode averages 9.3 cm, and the peduncle averages 10.6 cm in length, and 0.558 mm in thickness. The flag leaf averages 4.3 cm in length, 3.3 mm in width and 0.107 mm in thickness. The panicle has an average length of 7.6 cm, width of 4.2 cm, and 5.2 whorls. The lowest whorl has an average of 4.0 branches and the third whorl from the bottom of the panicle has an average of 2.7 branches. The average spikelet at the tip of a branch in the lowest whorl is 5.1 mm in length and has 3.9 florets with an outer glume of 2.9 mm and an inner glume of 3.3 mm in length. A similar spikelet from the third whorl from the bottom of the panicle is 5.0 mm in length and has 3.8 florets with an outer glume of 3.3 mm and an inner glume of 3.3 mm in length. After the seed has been conditioned, the lemma has a generally smooth keel with occasional short hairs and a few long fine hairs at the base. The seed of Ba 72-441 is 3.18 mm in length and 0.88 mm in width with approximately 1,003,037 seeds per pound. Comparisons of Ba 72-441 with other varieties on seed dimensions and on seed numbers per pound are shown in Tables 1 and 2.

                  TABLE 1                                                          ______________________________________                                         Seed Measurements of Ba 72-441 and Other Bluegrass                             Varieties After Conditioning.                                                                  Length  Width                                                  Variety         (mm)    (mm)                                                   ______________________________________                                         Ba 72-441       3.18    0.88                                                   Ba 70-139       2.86    0.78                                                   Ba 72-492       2.53    0.76                                                   Ba 72-500       2.77    0.80                                                   Baron           3.07    0.86                                                   Bristol         2.73    0.80                                                   Nassau          2.96    0.78                                                   Newport         2.76    0.71                                                   Park            3.04    0.72                                                   Ram I           3.51    0.84                                                   Victa           3.20    0.86                                                   LSD(.05)        0.19    0.06                                                   ______________________________________                                    

                  TABLE 2                                                          ______________________________________                                         Comparison of Seed Numbers Per Pound of Ba 72-441 and                          Other Bluegrass Varieties After Conditioning.                                             Number of Seeds                                                                Per Pound                                                           ______________________________________                                         Ba-72-441    1,003,037                                                         Ba 70-139    1,246,200                                                         Ba 72-492    1,275,740                                                         Ba 72-500    1,300,105                                                         Adelphi      1,383,976                                                         America      1,659,824                                                         Gnome        1,017,641                                                         Baron        1,051,693                                                         Birka        1,223,530                                                         Bonnieblue   1,135,303                                                         Bristol      1,270,821                                                         Eclipse      1,335,668                                                         Glade        1,108,441                                                         Kenblue      1,463,923                                                         Merit        1,109,728                                                         Nassau       1,127,130                                                         Newport      1,226,481                                                         Park         1,248,349                                                         Sydsport     1,355,644                                                         Vantage      1,555,303                                                         Victa        1,038,298                                                         Windsor      1,520,885                                                         ______________________________________                                    

Since environmental conditions such as soil and climate may influence morphological characters to some extent, comparisons of morphological characteristics of Ba 72-441 are made with other Kentucky bluegrass varieties in Tables 3-10.

                  TABLE 3                                                          ______________________________________                                         Morphological Comparison of Panicles of Ba 72-441 and                          Other Bluegrass Varieties in the Greenhouse at Marysville, Ohio.                                            Num-                                                                           ber of                                                                               Number of                                   Panicle    Panicle Panicle   Whorls                                                                               Branches                                           Nod-    Length  Width   Per   Lower Third                               Variety                                                                               ding*   (cm)    (cm)    Panicle                                                                              Whorl Whorl                               ______________________________________                                         Ba 72-441                                                                             1.4     7.6     4.2     5.2   4.0   2.7                                 Ba 70-139                                                                             2.0     6.7     3.7     4.8   3.8   2.7                                 Ba 72-492                                                                             1.2     7.5     4.2     5.5   4.0   3.0                                 Ba 72-500                                                                             2.0     6.8     3.8     5.0   4.0   2.4                                 Baron  1.0     7.8     4.1     5.2   3.8   2.5                                 Bristol                                                                               2.0     9.7     5.0     5.0   3.3   2.7                                 Nassau 2.0     10.0    6.0     5.0   3.0   2.0                                 Newport                                                                               2.0     10.3    4.4     4.5   2.3   2.3                                 Park   1.6     9.0     3.7     4.0   4.3   3.7                                 Ram I  2.0     9.0     4.7     4.0   2.5   2.0                                 Victa  1.2     7.5     4.1     5.4   4.4   3.4                                 LSD(.05)                                                                              0.5     1.6     1.0     0.8   0.7   0.8                                 ______________________________________                                          *Panicle nodding rated: 1 = erect, 2 = nodding.                          

                  TABLE 4                                                          ______________________________________                                         Morphological Comparison of Spikelets of Ba 72-441 and Other                   Bluegrass Varieties in the Greenhouse at Marysville, Ohio.                            Spikelet      Number of Florets                                                Length (mm)   per Spikelet                                                       Lowest    Third     Lowest  Third                                     Variety  Whorl     Whorl     Whorl   Whorl                                     ______________________________________                                         Ba 72-441                                                                               5.1       5.0       3.9     3.8                                       Ba 70-139                                                                               5.2       5.2       4.2     4.0                                       Ba 72-492                                                                               5.2       5.0       4.4     4.2                                       Ba 72-500                                                                               5.1       5.0       4.2     3.9                                       Baron    5.0       5.0       3.7     3.8                                       Bristol  6.2       6.0       5.7     5.3                                       Nassau   4.6       4.6       4.5     4.5                                       Newport  5.3       5.2       5.2     5.2                                       Park     6.5       6.7       5.2     4.7                                       Ram I    4.7       5.2       5.2     5.5                                       Victa    5.2       5.0       3.8     3.8                                       LSD(.05) 0.9       0.8       1.1     1.0                                       ______________________________________                                    

                  TABLE 5                                                          ______________________________________                                         Morphological Comparison of Glumes of Ba 72-441 and Other                      Bluegrass Varieties in the Greenhouse at Marysville, Ohio.                            Glume Length (mm)                                                              Outer         Inner                                                              Lowest    Third     Lowest  Third                                     Variety  Whorl     Whorl     Whorl   Whorl                                     ______________________________________                                         Ba 72-441                                                                               2.9       2.9       3.3     3.3                                       Ba 70-139                                                                               3.2       3.1       3.5     3.5                                       Ba 72-492                                                                               2.9       3.0       3.3     3.3                                       Ba 72-500                                                                               3.1       3.1       3.4     3.4                                       Baron    2.9       2.8       3.4     3.3                                       Bristol  3.4       3.3       3.7     3.9                                       Nassau   2.3       2.4       2.7     2.7                                       Newport  2.6       2.5       2.9     2.9                                       Park     3.0       3.2       3.5     3.7                                       Ram I    2.6       2.4       2.9     2.7                                       Victa    2.8       3.0       3.3     3.3                                       LSD(.05) 0.5       0.4       0.4     0.4                                       ______________________________________                                    

                  TABLE 6                                                          ______________________________________                                         Morphological Comparison of Flag Leaves of Ba 72-441 and                       Other Bluegrass Varieties in the Greenhouse at Marysville, Ohio.                        Flag Leaf    Flag Leaf Flag Leaf                                               Length       Width     Thickness                                      Variety  (cm)         (mm)      (mm)                                           ______________________________________                                         Ba 72-441                                                                               4.3          3.3       0.107                                          Ba 70-139                                                                               4.7          3.2       0.112                                          Ba 72-492                                                                               5.2          3.6       0.117                                          Ba 72-500                                                                               4.1          3.2       0.112                                          Baron    4.5          3.2       0.119                                          Bristol  5.5          3.4       0.127                                          Nassau   6.2          3.1       0.127                                          Newport  6.1          3.5       0.135                                          Park     4.2          2.6       0.109                                          Ram I    4.7          3.1       0.127                                          Victa    5.9          4.0       0.124                                          LSD(.05) 1.8          0.6       0.013                                          ______________________________________                                    

                  TABLE 7                                                          ______________________________________                                         Morphological Comparison of Peduncles, Culms, and                              Internodes of Ba 72-441 and Other Bluegrass Varieties                          in the Greehouse at Marysville, Ohio.                                                                                 Top                                            Peduncle Peduncle Culm  Number of                                                                              Internode                                      Length   Width    Length                                                                               Nodes Per                                                                              Length                                  Variety                                                                               (cm)     (mm)     (mm)  Culm    (cm)                                    ______________________________________                                         Ba 72-441                                                                             10.6     0.558    421   2.7     9.3                                     Ba 70-139                                                                             13.2     0.610    435   2.7     10.2                                    Ba 72-492                                                                             12.6     0.558    486   2.2     10.5                                    Ba 72-500                                                                             12.9     0.660    439   2.7     9.8                                     Baron  12.7     0.559    482   2.5     10.1                                    Bristol                                                                               15.0     0.686    522   2.7     11.3                                    Nassau 8.0      0.533    450   2.5     11.2                                    Newport                                                                               18.0     0.558    547   2.3     11.2                                    Park   14.3     0.787    578   3.0     13.0                                    Ram I  18.5     0.610    527   3.0     10.2                                    Victa  12.2     0.711    474   2.4     10.6                                    LSD(.05)                                                                              3.7      0.018     79   0.6     2.1                                     ______________________________________                                    

                  TABLE 8                                                          ______________________________________                                         Morphological Comparison of Leaves of Ba 72-441 and Other                      Bluegrass Varieties in the Greenhouse at Marysville, Ohio.                                                      Leaf                                                  Ligule   Leaf     Leaf   Angle                                                 Length   Length   Width  (Degrees                                      Variety (mm)     (mm)     (mm)   From Horizontal)                              ______________________________________                                         Ba 72-441                                                                              0.23     218      3.9    56                                            Ba 70-139                                                                              0.26     218      4.1    55                                            Ba 72-492                                                                              0.28     239      4.4    52                                            Ba 72-500                                                                              0.25     204      4.1    50                                            Baron   0.30     313      4.4    63                                            Bristol 0.30     253      4.3    37                                            Nassau  0.22     226      3.5    39                                            Newport 0.22     251      4.1    50                                            Park    0.33     329      4.2    44                                            Ram I   0.18     188      3.7    40                                            Victa   0.28     235      4.3    52                                            LSD(.05)                                                                               0.11      49      0.6    10                                            ______________________________________                                    

                  TABLE 9                                                          ______________________________________                                         Morphological Comparison of Leaf Hairs of Ba 72-441 and                        Other Bluegrass Varieties in the Greenhouse at Marysville, Ohio.                        Hairs.sup.a Around                                                             Ligule on                                                                      Upper Surface  Hairs.sup.a on                                                                          Hairs.sup.b on                                Variety  of the Leaf    Collar   Ligule                                        ______________________________________                                         Ba 72-441                                                                               1.0            3.4      2.2                                           Ba 70-139                                                                               1.0            3.5      1.5                                           Ba 72-492                                                                               1.0            3.2      1.3                                           Ba 72-500                                                                               1.0            3.5      2.7                                           Baron    1.0            5.0      4.0                                           Bristol  1.3            4.7      4.3                                           Nassau   2.7            5.0      1.0                                           Newport  1.0            4.0      0.8                                           Park     1.0            1.7      0.0                                           Ram I    1.0            3.7      0.3                                           Victa    1.0            3.3      2.2                                           LSD(.05) 0.3            1.4      1.8                                           ______________________________________                                          .sup.a Hairs around ligule and on collar rated 1-5: 1 = none, 5 = many.        .sup.b Hairs on ligule rated 0-5: O = none, 5 = many.                    

                  TABLE 10                                                         ______________________________________                                         Morphological Comparisons of Ba 72-441 and Other Bluegrass                     Varieties Grown as Unmowed Spaced Plants in the Field at                       Marysville, Ohio.                                                              Mature                                                                         Plant Height   Panicle Density                                                                            Seedhead Weight                                     ______________________________________                                         Ba 72-441                                                                             38          7           656                                             Ba 70-139                                                                             35          5           402                                             Adelphi                                                                               42          3           345                                             Nugget 17          3           233                                             Bristol                                                                               40          4           511                                             Merion 25          2           320                                             Glade  20          3           214                                             Vantage                                                                               52          2           1019                                            Victa  23          2           648                                             ______________________________________                                          Ratings: Mature Plant Height (cm) includes panicle.                            Panicle Density  1-10, 10 = high panicle density.                              Seedhead Weight  Weight (mg) of 3 panicles.                              

Ba 72-441 has performed well throughout the U.S.A., as exhibited by high turf quality ratings in many different locations in comparison to other varieties. In addition, it has a pleasant medium green color which can be maintained throughout the growing season, good winter color, and early spring greening. Comparisons of Ba 72-441 with other varieties for quality and color are shown in Tables 11-14.

                  TABLE 11                                                         ______________________________________                                         Comparison of the Turf Quality of Ba 72-441 and Other                          Bluegrass Varieties in the U.S.A.                                                           Lin-                Marysville,                                   Adelphia     coln    Maryland    Ohio                                                  New      Nebra-  Belts-                                                                               Acco- Test  Test                                        Jersey   ska     ville keek  1     2                                           2 Year   2 Year  1 Year                                                                               3 Year                                                                               5 Year                                                                               5 Year                              Variety Mean     Mean    Mean  Mean  Mean  Mean                                ______________________________________                                         Ba 72-441                                                                              6.6      6.0     5.9   2.7   2.7   2.4                                 A-34             6.2     5.6                                                   Adelphi 6.4      6.1     5.9   2.4   2.7                                       Banff                    4.8                                                   Baron   6.4      5.6     5.3   2.4                                             Birka   5.9      5.9           1.8                                             Bonnieblue                                                                             6.7      5.8     5.0   2.3                                             Bono                           1.9                                             Bristol 6.5      5.9     5.0   2.3   2.7   2.3                                 Eclipse 7.2      5.8     5.9                                                   Fylking 5.7      6.1     4.9               2.1                                 Geary   3.6                                                                    Glade   6.7      6.4     5.3                                                   Kenblue 3.3                    1.8         2.0                                 Merion  6.0      5.9     5.3               2.2                                 Merit   6.2      6.0     6.1   2.3         2.2                                 Midnight                                                                               7.3      5.9     5.5   2.4                                             Monopoly                                                                               5.7              4.9                                                   Nassau  5.9              4.5                                                   Newport                                    2.1                                 Parade  5.6      6.5     5.0         2.7                                       Park             5.7           2.0   2.1                                       Ram I   6.2      5.9     4.6   2.4                                             Rugby                          2.2                                             Shasta  5.7                                                                    Sydsport                                                                               6.0      6.3     5.8               2.2                                 Touchdown                                                                              6.1      5.9     5.8                                                   Trenton                        2.4                                             Vantage 3.6      5.8     5.5   2.3   2.6   2.0                                 Victa   6.5      5.7     5.5   2.3   2.6   2.3                                 Wabash  4.8                                                                    ______________________________________                                          Rating Scale: Larger number indicates higher quality.                    

                  TABLE 12                                                         ______________________________________                                         Comparison of Turf Color of Ba 72-441 and Other                                Bluegrass Varieties at Various Locations in the U.S.A.                                 St. Louis                                                                               Lincoln  Marysville                                                                             Prince Frederick                             Variety Missouri Nebraska Ohio    Maryland                                     ______________________________________                                         Ba 72-441                                                                              9.1      7.0      8.3     7.5                                          A-34             6.5                                                           Adelphi 9.4      7.2      8.4     7.8                                          America 9.4      7.0      8.5                                                  Baron   9.2      6.9      8.5     7.3                                          Birka   9.1      6.7      8.1     7.0                                          Bonnieblue       7.0              7.7                                          Bono    9.0                       6.6                                          Bristol 9.5      7.3      8.9     7.4                                          Eclipse          7.0      8.5                                                  Fylking          6.8                                                           Glade   9.3      7.1      8.4                                                  Kenblue                   8.1     5.9                                          Merion           6.9                                                           Merit   9.2      7.0              6.8                                          Midnight         7.9      8.9     7.4                                          Newport                                                                        Parade           6.8                                                           Park    9.0      6.1      8.1     6.6                                          Ram I            7.3              7.8                                          Rugby            6.8              7.9                                          Sydsport                                                                               9.2      7.0      8.2                                                  Touchdown                                                                              9.0      6.8      8.1                                                  Vantage 9.2      6.8      8.5     7.7                                          Victa   9.2      6.9      8.4     7.1                                          Wabash                            7.0                                          LSD(.05)                                                                               0.3      --       --      --                                           ______________________________________                                          Rating Scale: Larger number indicates darker green color.                

                  TABLE 13                                                         ______________________________________                                         Winter Color of Ba 72-441 and Other Bluegrass Varieties.                                  Gervais, Oregon                                                                             Marysville, Ohio                                       Variety    2 Year Mean  1 Year Mean                                            ______________________________________                                         Ba 72-441  4.8          2.7                                                    Adelphi    --           2.0                                                    Bristol    5.4          6.7                                                    Parade     --           3.8                                                    Park       --           1.2                                                    Vantage    --           1.7                                                    Victa      3.4          2.7                                                    LSD(.05)   0.9          --                                                     ______________________________________                                          Rated 1-9: 9 = darkest green color.                                      

                  TABLE 14                                                         ______________________________________                                         Spring Greening of Ba 72-441 and Other Bluegrass Varieties.                               Maryland                                                            Lincoln      Prince    Belts-  Marysville, Ohio                                Variety Nebraska Frederick ville Test 1 Test 2                                 ______________________________________                                         Ba 72-441                                                                              6.0      7.0       5.3   5.3    3.5                                    A-34    5.0                5.3                                                 Adelphi 6.8      7.0       4.7   7.7    2.8                                    America 4.8                4.7   6.3                                           Banff                      5.3                                                 Baron   5.3      7.0       4.3   3.0                                           Birka   5.0      7.3       4.7   5.7                                           Bonnieblue                                                                             5.3      7.0                                                           Bono             8.3                                                           Bristol 5.5      7.3       4.7   5.7    4.2                                    Cheri   4.8                4.3                                                 Eclipse 5.5                5.7   6.5                                           Enmundi 5.3                4.7                                                 Fylking 4.8                4.7                                                 Geronimo                   6.3                                                 Glade   5.3                5.3   5.0                                           Kenblue          6.3       3.3   8.0                                           Merion  5.0                4.0                                                 Merit   5.5      6.0       4.3                                                 Midnight                                                                               4.8      7.0       4.7   2.0                                           Monopoly                   5.3                                                 Nassau                     7.7                                                 Nugget                     2.3                                                 Parade  5.5                4.3          3.2                                    Park    5.8      6.0             7.7    2.5                                    Ram I   5.5      7.7       6.5                                                 Rugby   5.0      7.0                                                           Shasta                     5.3                                                 Sydsport                                                                               4.8                4.7   5.3                                           Touchdown                                                                              5.3                4.3   5.7                                           Vantage 5.8      7.7       5.0   8.0    3.0                                    Victa   5.8      5.7       3.7   4.3    3.0                                    Wabash           6.7       5.3                                                 LSD     0.8      1.8             1.6                                           ______________________________________                                          Rated 1-9: 9 = darkest green color.                                      

Turf diseases are one of the major causes of inconsistent and poor turf performance among locations and years. Ba 72-441 has been found to have a high level of resistance to leaf spot (also known as melting out and crown rot) caused by Helminthosporium vagans, a medium to high level of resistance to rust caused by Puccinia spp., a medium level of resistance to dollarspot caused by Sclerotina homeocarpa, and a high level of resistance to stripe smut caused by Ustilago striiformis.

Resistance to stripe smut was determined in tests in Ohio and Maryland where Ba 72-441 and the standard varieties included in the tests had little or no incidence of stripe smut but several experimental selections were heavily infected. Comparisons of resistance to leaf spot, rust, and dollarspot are presented in Tables 15-17.

                  TABLE 15                                                         ______________________________________                                         Comparison of Leafspot Disease Incidence on Ba 72-441 and                      Other Bluegrasses at Several Locations in the U.S.A.                           St.                              Marysville,                                   Louis.sup.a  Beltsville.sup.b                                                                         Adelphia.sup.b                                                                           Ohio.sup.a                                    Variety Missouri Maryland  New Jersey                                                                             Test 1                                                                               Test 2                                ______________________________________                                         Ba 72-441                                                                              2        8.0       8.0     6     42                                    A-34             5.3       4.3                                                 Adelphi 2        8.0       5.7     9     75                                    America 8                                43                                    Banff            5.3       7.0                                                 Baron   2        7.0       8.7           42                                    Birka   5                  6.3           58                                    Bonnieblue                 7.0                                                 Bono    7                                63                                    Bristol 2        7.0       8.3     5     43                                    Eclipse          7.7       9.0           80                                    Fylking          6.7       6.3                                                 Geary                      2.0                                                 Glade   2        7.3       6.3           38                                    Kenblue          3.3       1.7           93                                    Merion           6.1       7.7                                                 Merit   3        7.3       7.7                                                 Midnight         7.0       7.0                                                 Monopoly         5.3       6.0                                                 Nassau           7.7       7.4                                                 Parade           6.0       5.0     10                                          Park    52                         54    95                                    Ram I            6.5       7.0                                                 Rugby                      5.0                                                 Shasta                     6.0                                                 Sydsport                                                                               3        7.3       6.3           48                                    Touchdown                                                                              7        7.7                     57                                    Trenton                    6.0                                                 Vantage 7        5.0       2.0     15    90                                    Victa   2        8.0       7.0     7     22                                    Wabash                     2.0                                                 LSD(.05)                                                                               7                  1.9           34                                    ______________________________________                                          Ratings                                                                        .sup.a % of turf affected by disease.                                          .sup.b 1-9: 9 = least disease.                                           

                  TABLE 16                                                         ______________________________________                                         Comparison of Rust (Puccinia spp.) Disease Incidence on                        Ba 72-441 and Other Bluegrasses.                                                       Adelphia.sup.a                                                                           Gervais, Oregon                                              Variety   New Jersey  Turf.sup.b                                                                             Seed Production.sup.c                            ______________________________________                                         Ba 72-441 7.0         43      2.0                                              Adelphi   7.1                                                                  America   7.4                                                                  Banff     6.5                                                                  Baron     6.4                                                                  Birka     3.5                                                                  Bonnieblue                                                                               5.4                                                                  Bristol   7.7          7      4.0                                              Eclipse   4.7                                                                  Julia                         4.0                                              Merion    2.4                                                                  Merit     5.7                                                                  Midnight  7.0                                                                  Monopoly  7.1                                                                  Mosa                          4.0                                              Nassau    6.8                                                                  Newport                       4.0                                              Parade    6.2                                                                  Ram I     7.0                                                                  Touchdown 3.5                                                                  Vantage   6.2                                                                  Victa     5.6         63      2.0                                              LSD(.05)  0.9                                                                  ______________________________________                                          Ratings:                                                                       .sup.a Stem Rust (Puccinia graminis Pers.)0-9: 9 = no disease.                 .sup.b % of turf affected by disease.                                          .sup.c 1-4: 4 = very susceptible.                                        

                  TABLE 17                                                         ______________________________________                                         Comparison of Dollarspot Disease Incidence on Ba 72-441                        and Other Bluegrasses. -                                                                        Prince Frederick                                                                            Marysville                                       Variety                                                                            Maryland     Ohio                                                          ______________________________________                                         Ba 72-441    15           27                                                   Adelphi      8            20                                                   America                   13                                                   Baron        50           23                                                   Birka        6            47                                                   Bonnieblue   10                                                                Bono         4            63                                                   Bristol      6            17                                                   Eclipse                    8                                                   Glade                     40                                                   Kenblue      8            37                                                   Merit        4                                                                 Midnight     6                                                                 Park                      33                                                   Ram I        40                                                                Rugby        12                                                                Sydsport                  43                                                   Touchdown                 50                                                   Trenton      28                                                                Vantage      11           15                                                   Victa        5            23                                                   Wabash       11                                                                LSD(.05)     19           24                                                   ______________________________________                                          Rating: % of turf affected by disease.                                   

Ba 72-441 has the capability to tolerate heat and drought stress. In addition, it has a low growth habit and a slower vertical growth rate than many varieties, especially the common type of varieties such as Park, Newport, and Kenblue, that should allow it to tolerate lower mowing heights and possibly decrease the total number of mowings per year without sacrificing overall turf performance. The leaf texture of the new variety is similar to many bluegrass varieties when maintained under mowed turf conditions. Comparisons showing tolerance to drought and heat stress, growth habit, and leaf texture are presented in Tables 18-20.

                  TABLE 18                                                         ______________________________________                                         Comparison of Drought and Heat Tolerance of Ba 72-441                          and Other Bluegrasses.                                                                      Prince Frederick                                                                            Marysville                                           Variety      Maryland     Ohio                                                 ______________________________________                                         Ba 72-441    2             1                                                   Adelphi      12           18                                                   Baron        10                                                                Birka        5                                                                 Bonnieblue   4                                                                 Bono         13                                                                Bristol      11            8                                                   Kenblue      15                                                                Merit        7                                                                 Midnight     13                                                                Parade                    27                                                   Park         7            13                                                   Ram I        6                                                                 Rugby        9                                                                 Vantage      10            8                                                   Victa        9            13                                                   Wabash       9                                                                 ______________________________________                                          Rated as % turf losing healthy green color.                              

                  TABLE 19                                                         ______________________________________                                         Comparison of Growth Habit of Ba 72-441 and Other Bluegrass                    Varieties Under Mowed Conditions at Marysville, Ohio.                                   Test 1.sup.a                                                          Variety    Year 1       Year 2  Test 2.sup.b                                   ______________________________________                                         Ba 72-441  79           61      1.7                                            Adelphi                         2.7                                            Bristol    69           73      2.0                                            Fylking    95           80                                                     Kenblue    96           81                                                     Merion     76           71                                                     Merit      86           76                                                     Newport    92           78                                                     Parade                          2.3                                            Park                            2.3                                            Sydsport   70           64                                                     Vantage    85           65      2.0                                            Victa      81           64      2.0                                            LSD(.05)   15           13      0.6                                            ______________________________________                                          Rating:                                                                        .sup.a Height (mm) of turf about one week after last mowing.                   .sup.b 0-9: 9 = very tall growing turf, 0 = no growth since last mowing. 

                  TABLE 20                                                         ______________________________________                                         Comparison of Leaf Texture of Ba 72-441 and Other                              Bluegrasses Under Mowed Turf Conditions.                                                      St. Louis                                                                               Marysville                                             Variety        Missouri Ohio                                                   ______________________________________                                         Ba 72-441      4.6      5.0                                                    Adelphi        5.3                                                             America        6.0                                                             Baron          4.6                                                             Birka          6.0                                                             Bono           5.6                                                             Bristol        5.3      5.0                                                    Fylking                 5.8                                                    Glade          6.0                                                             Kenblue                 5.5                                                    Merion                  5.0                                                    Merit          4.3      5.0                                                    Newport                 5.0                                                    Park           6.0                                                             Sydsport       5.0      5.0                                                    Touchdown      5.0                                                             Vantage        6.0      5.3                                                    Victa          4.4      4.8                                                    LSD(.05)       0.7      0.4                                                    ______________________________________                                          Rating: 1-9: 9 = narrowest leaf blade.                                   

The new variety has a very high level of seed yielding potential which will make it economical to produce and aid in its commercial success. Comparative results on seed yield are shown in Table 21.

                  TABLE 21                                                         ______________________________________                                         Seed Yield Comparisons of Ba 72-441 and Other Bluegrass                        Varieties in Oregon.                                                           Location Gervais             LaGrande                                          Harvest Year                                                                            Year 1  Year 2  Mean  Year 1                                                                               Year 2                                                                               Mean                                ______________________________________                                         Variety                                                                        Ba 72-441                                                                               691     1586    1139  1512  1253  1383                                Victa    780     1394    1087  1419  1200  1310                                Newport  435     1256    846                                                   Bristol  347      808    578   1089   970  1030                                Mosa     322     1060    691                                                   Julia    296     1016    656                                                   LSD(.05) 140      134           149   181   220                                ______________________________________                                          Rating: Pounds per acre of conditioned seed.                              

What is claimed is:
 1. A variety of Kentucky bluegrass plant, substantially as shown and described, characterized by a high level of resistance to disease, especially leaf spot disease, a desirable green color throughout the growing season, a high quality persistent turf under a wide variety of environmental conditions and a very high level of seed yielding capacity. 